Vulnerability · CVE-2025-37856
In the Linux kernel, the following vulnerability has been resolved: btrfs: harden block_group::bg_list against list_del() races As far as I can tell, these calls of list_del_init()
Published May 9, 2025 · catalog updated Aug 5, 2026 · Linux Linux
Check if you run it
No confirmed exploitation is on record for CVE-2025-37856. EPSS is 0.28%. Act only if a listed version of Linux Linux is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.28%
- Remediation
- Version ranges on file
- Affected products
- vendor Linux Linux a9f189716cf15913c453299d72f69c51a9b0f86b <bf089c4d1141b27332c092b1dcca5022c415a3b6
In the Linux kernel, the following vulnerability has been resolved: btrfs: harden block_group::bg_list against list_del() races As far as I can tell, these calls of list_del_init() on bg_list cannot run concurrently with btrfs_mark_bg_unused() or btrfs_mark_bg_to_reclaim(), as they are in transaction error paths and situations where the block group is readonly. However, if there is any chance at all of racing with mark_bg_unused(), or a different future user of bg_list, better to be safe than sorry. Otherwise we risk the following interleaving (bg_list refcount in parens) T1 (some random op) T
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Linux Linux a9f189716cf15913c453299d72f69c51a9b0f86b <bf089c4d1141b27332c092b1dcca5022c415a3b6a9f189716cf15913c453299d72f69c51a9b0f86b <bf089c4d1141b27332c092b1dcca5022c415a3b6
How to fix CVE-2025-37856
Recommended remediation
Affected version ranges suggest a fixed boundary. Verify against the vendor advisory for your release.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-37856. EPSS is 0.28%. Act only if a listed version of Linux Linux is installed.
Which versions are affected?
Compare what you have installed with Linux Linux a9f189716cf15913c453299d72f69c51a9b0f86b <bf089c4d1141b27332c092b1dcca5022c415a3b6 a9f189716cf15913c453299d72f69c51a9b0f86b <bf089c4d1141b27332c092b1dcca5022c415a3b6. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.28%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 9, 2025 · EUVD
Detected
In the Linux kernel, the following vulnerability has been resolved: btrfs: harden block_group::bg_list against list_del() races As far as I can tell, these calls of list_del_init() on bg_list cannot run concurrently with btrfs_mark_bg_unused() or btrfs_mark_bg_to_reclaim(), as they are in transaction error paths and situations where the block group is readonly. However, if there is any chance at a
Aug 5, 2026 · EUVD
Updated
In the Linux kernel, the following vulnerability has been resolved: btrfs: harden block_group::bg_list against list_del() races As far as I can tell, these calls of list_del_init() on bg_list cannot run concurrently with btrfs_mark_bg_unused() or btrfs_mark_bg_to_reclaim(), as they are in transaction error paths and situations where the block group is readonly. However, if there is any chance at a
Sources
- CVE.orgVulnerability recordCVE-2025-37856
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-37856
30-day exploitation probability 0.3%
first.org - EUVDVulnerability recordEUVD-2025-14136
In the Linux kernel, the following vulnerability has been resolved: btrfs: harden block_group::bg_list against list_del() races As far as I can tell, these calls of list_del_init() on bg_list cannot run concurrently with btrfs_mark_bg_unused() or btrfs_mark_bg_to_reclaim(), as th
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.